A solar cell utilizing sunlight as an alternative energy source to a fossil fuel such as petroleum, coal or the like has been paid attention to. Efficiency-enhancement studies have been conducted enthusiastically nowadays for the development and improvement of a silicon solar cell wherein used crystalline or amorphous silicon; or a compound semiconductor solar cell wherein used gallium, arsenic or the like. However, they have not widely been accepted in the market because of the high production cost and energy-consumingness as well as the difficulties relating to the resources problem. Due to the above, the development of cost-effective solar cell has been desired. At the same time, a photoelectric conversion device comprising semiconductor fine particles sensitized with dye(s) and a solar cell comprising the said photoelectric conversion device have been known, whereupon disclosed materials and techniques for producing the same. (B. O'Regan and M. Gratzel Nature, 353, 737 (1991), M. K. Nazeeruddin, A. Kay, I. Rodicio, R. Humphry-Baker, E. Muller, P. Liska, N. Vlachopoulos, M. Gratzel, J. Am. Chem. Soc., 115, 6382 (1993) e.t.c.). This photoelectric conversion device produced by using the low-cost oxide semiconductor such as titanium oxide has attracted the public attention as there is a possibility to obtain an inexpensive photoelectric conversion device compared to the solar cell produced by using a conventional material such as silicon. However, there still lies ahead a problem relating to the material of the sensitizing-dye, for which a ruthenium-type complex, high in cost and low in supply, is used in order to pursue a high conversion efficiency in the device. Although some attempts have been made to utilize an organic dye for the sensitizing-dye, they have not yet been put into practical use at present due to the difficulties such as low conversion efficiency.
In regard to the photoelectric conversion device comprising organic dye-sensitized semiconductor, a development of a practical photoelectric conversion device having high conversion efficiency and stability by using an inexpensive organic dye is desired.